I think if you're wanting a big power CPU year, this is it if you can pony up for the M3 Max.
If you want a big GPU year, I think next year may be it. Although I think we haven't seen all of the benefits of RT yet.
I don't see the M4, also being on 3nm+, being much faster. I don't think there is a lot of thermal headroom for it, except maybe on the lower and mid tier CPUs. But I feel like they didn't do a ton with the raw GPU performance this year, so they will optimize it a lot more next year and beef it up.